My daughter and son and law want to refinance their house, but credit score is not very good, they want to add me to the deed to raise the credit score and show more income. Is this possible to do?

You will be on the mortgage and the deed, so this may do a few things.First if they don't pay for some reason they can come after you for payment, so are you able and ready to make their house payments if they don't.This may also effect the property tax status and their homestead exemptions and need to be reviewed